From fc9a77040b04c05f036515f40aa7cf4b9c91defd Mon Sep 17 00:00:00 2001 From: Kishon Vijay Abraham I Date: Mon, 25 Mar 2019 15:09:44 +0530 Subject: [PATCH] PCI: designware-ep: Configure Resizable BAR cap to advertise the smallest size Configure the Resizable BAR capability to advertise the smallest size (1MB) for a couple of reasons: - Host side resource allocation of BAR fails for larger sizes - Endpoint function driver does not allocate memory for all supported sizes in the Resizable BAR capability. If and when there is a usecase required to add more flexibility using the Resizable BAR capability, this can be revisited. Signed-off-by: Kishon Vijay Abraham I [lorenzo.pieralisi@arm.com: updated commit log] Signed-off-by: Lorenzo Pieralisi --- .../pci/controller/dwc/pcie-designware-ep.c | 34 +++++++++++++++++++ 1 file changed, 34 insertions(+) diff --git a/drivers/pci/controller/dwc/pcie-designware-ep.c b/drivers/pci/controller/dwc/pcie-designware-ep.c index 74477ad7467f..0c208b9bda43 100644 --- a/drivers/pci/controller/dwc/pcie-designware-ep.c +++ b/drivers/pci/controller/dwc/pcie-designware-ep.c @@ -504,10 +504,32 @@ void dw_pcie_ep_exit(struct dw_pcie_ep *ep) pci_epc_mem_exit(epc); } +static unsigned int dw_pcie_ep_find_ext_capability(struct dw_pcie *pci, int cap) +{ + u32 header; + int pos = PCI_CFG_SPACE_SIZE; + + while (pos) { + header = dw_pcie_readl_dbi(pci, pos); + if (PCI_EXT_CAP_ID(header) == cap) + return pos; + + pos = PCI_EXT_CAP_NEXT(header); + if (!pos) + break; + } + + return 0; +} + int dw_pcie_ep_init(struct dw_pcie_ep *ep) { + int i; int ret; + u32 reg; void *addr; + unsigned int nbars; + unsigned int offset; struct pci_epc *epc; struct dw_pcie *pci = to_dw_pcie_from_ep(ep); struct device *dev = pci->dev; @@ -591,6 +613,18 @@ int dw_pcie_ep_init(struct dw_pcie_ep *ep) ep->msix_cap = dw_pcie_ep_find_capability(pci, PCI_CAP_ID_MSIX); + offset = dw_pcie_ep_find_ext_capability(pci, PCI_EXT_CAP_ID_REBAR); + if (offset) { + reg = dw_pcie_readl_dbi(pci, offset + PCI_REBAR_CTRL); + nbars = (reg & PCI_REBAR_CTRL_NBAR_MASK) >> + PCI_REBAR_CTRL_NBAR_SHIFT; + + dw_pcie_dbi_ro_wr_en(pci); + for (i = 0; i < nbars; i++, offset += PCI_REBAR_CTRL) + dw_pcie_writel_dbi(pci, offset + PCI_REBAR_CAP, 0x0); + dw_pcie_dbi_ro_wr_dis(pci); + } + dw_pcie_setup(pci); return 0; -- 2.45.2